Soldiers help carry the bodies of workers killed in the fire at a garment factory in Dhaka. Photograph: Jibon Amir/AP

Blazes like the one in Dhaka on Saturday, which killed at least 120 in a garment factory, are sadly all too frequent occurrences around south Asia.

In September, in one of the worst incidents of its kind, 289 died in Karachi, Pakistan. The same month, 40 were killed in a blaze at a fireworks factory in the state of Tamil Nadu in south India.

Several factors combine to make death traps of factories across south Asia. Often exits are padlocked, basements used as store rooms for highly flammable raw materials and fire escapes missing. Smoke alarms and sprinkler systems are rarely heard of.

Survivors often describe the desperate crush as hundreds rush into narrow corridors filled with clouds of toxic smoke.

Fire is a constant hazard in the grossly overcrowded poor neighbourhoods of emerging world cities.

There is little proper zoning so industry is sited in the middle of residential areas, often slums which house the factory workers. More than 120 died in June 2010 when a fire destroyed six buildings – including a factory – in Dhaka. A possible cause was cooking for a wedding.

Then there is the ill-preparedness. Fire services in south Asia are poorly equipped and trained, and public awareness is low. "The workers are not trained to use extinguishers. The fire drills performed at the factories are limited to attaining only the benchmark of compliance and audits," said Kalpona Akter of the Bangladesh Centre for Workers' Solidarity (BCWS).

Babul Akhter, president of the Bangladesh garments and industrial workers' federation, said mid-level managers were mostly concerned with how many clothes could be produced and forgot safety.

Then there is corruption, endemic in all south Asian nations, which means government inspectors are easily paid off. The ease of hiring and firing, and mobility of the workforce, means "no employee-employer relationship", according to Subhash Bhatnagar of the Delhi-based Unorganised Workers Association. "There is no sense of safeguarding their wellbeing," he said. Construction sites present another major problem. Bhatnagar estimates that hundreds die every year in Delhi alone, and thousands across the rest of India and Bangladesh in building site accidents.

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